Clostridioides difficile is a One Health pathogen found in humans, animals, and environment, with food representing a potential transmission route. One Health studies are often limited to single country or selected reservoirs and ribotypes. This study provides a varied and accessible collection of C. difficile isolates and sequencing data derived from human, animal, and food sources across thirteen European countries. A total of 441 strains (human hospital and community associated cases n = 280, animal n = 96, food n = 65) were analysed by ribotyping, toxinotyping and whole genome sequencing (WGS). We detected 83 sequence types (STs), with ST11 (n = 80 isolates) and ST1 (n = 54 isolates) being the most represented. Several STs included strains originating from all source combinations. Further genomic analysis confirmed close genetic relatedness in some of the STs. Additionally, genomic analysis identified ten strains from cryptic clades (C-I to C-III) and four of them were mono-toxigenic possessing only a variant form of tcdA gene. Amongst 106 ribotypes, ten were shared between all three sources and 68 were source specific. Some ribotypes were only found at intersection of human and food source (RT023, RT027), or between human and animal source (RT009, RT045, RT046). C. difficile ribotypes and STs in Europe were diverse. In this collection some ribotypes showed potential association with food or animal transmission routes. C. difficile strains from divergent clades CI-III, currently emerging in human population, were rare and mostly food associated.
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